Question:

Which statement is the best analogy?
A. An umbrella is to rain as the stratosphere is to solar radiation.
B. An umbrella is to rain as the stratosphere is to ultraviolet radiation.
C. An umbrella is to rain as the ozone layer is to solar radiation.
D. An umbrella is to rain as the ozone layer is to ultraviolet radiation.

Student Responses:

These responses were collected from students (mostly freshmen, non-majors) in multiple large Earth Science classes (60+ students) at an open-enrollment, Midwestern university. N=147 students on first attempt; 157 after peer instruction.
A. 12% of students selected this answer on their 1st attempt; 4% after peer instruction.
B. 18% of students selected this answer on their 1st attempt; 5% after peer instruction.
C. 26% of students selected this answer on their 1st attempt; 11% after peer instruction.
D. 44% of students selected this answer on their 1st attempt; 80% after peer instruction.(correct)

References and Notes:

The use of ConcepTests and Peer Instruction is discussed in detail on the ConcepTest page.